private void DropEdge(EdgeField edgeField)
{
RawRecord record = new RawRecord();
record.Append(new StringField(edgeField.OutV)); // srcIdIndex
record.Append(new StringField(edgeField.Offset.ToString())); // edgeOffsetIndex
DropEdgeOperator op = new DropEdgeOperator(this.dummyInputOp, this.connection, 0, 1);
op.DataModify(record);
// Now VertexCacheObject has been updated (in DataModify)
}
internal override GraphViewExecutionOperator Compile(QueryCompilationContext context, GraphViewConnection dbConnection)
{
var srcIdParameter = Parameters[0] as WColumnReferenceExpression;
var edgeOffsetParameter = Parameters[1] as WColumnReferenceExpression;
var srcIdIndex = context.LocateColumnReference(srcIdParameter);
var edgeOffsetIndex = context.LocateColumnReference(edgeOffsetParameter);
var dropEdgeOp = new DropEdgeOperator(context.CurrentExecutionOperator, dbConnection, srcIdIndex, edgeOffsetIndex);
context.CurrentExecutionOperator = dropEdgeOp;
return(dropEdgeOp);
}
// TODO: Batch upload for the DropEdge part
internal override RawRecord DataModify(RawRecord record)
{
string vertexId = record[this._nodeIdIndex].ToValue;
// Temporarily change
DropEdgeOperator dropEdgeOp = new DropEdgeOperator(null, this.Connection, 0, 1);
RawRecord temp = new RawRecord(2);
VertexField vertex = this.Connection.VertexCache.GetVertexField(vertexId);
// Save a copy of Edges _IDs & drop outgoing edges
List <long> outEdgeOffsets = vertex.AdjacencyList.AllEdges.Select(e => e.Offset).ToList();
foreach (long outEdgeOffset in outEdgeOffsets)
{
temp.fieldValues[0] = new StringField(vertexId);
temp.fieldValues[1] = new StringField(outEdgeOffset.ToString());
dropEdgeOp.DataModify(temp);
}
AdjacencyListField revAdjacencyListField = Connection.UseReverseEdges
? vertex.RevAdjacencyList
: EdgeDocumentHelper.GetReverseAdjacencyListOfVertex(Connection, vertexId);
// Save a copy of incoming Edges <srcVertexId, edgeOffsetInSrcVertex> & drop them
List <Tuple <string, long> > inEdges = revAdjacencyListField.AllEdges.Select(
e => new Tuple <string, long>(e.OutV, e.Offset)).ToList();
foreach (var inEdge in inEdges)
{
temp.fieldValues[0] = new StringField(inEdge.Item1); // srcVertexId
temp.fieldValues[1] = new StringField(inEdge.Item2.ToString()); // edgeOffsetInSrcVertex
dropEdgeOp.DataModify(temp);
}
// Delete the node-document!
#if DEBUG
JObject vertexObject = this.Connection.RetrieveDocumentById(vertexId);
Debug.Assert(vertexObject != null);
Debug.Assert(vertexObject["_edge"] is JArray);
Debug.Assert(((JArray)vertexObject["_edge"]).Count == 0);
Debug.Assert(vertexObject["_reverse_edge"] is JArray);
Debug.Assert(((JArray)vertexObject["_reverse_edge"]).Count == 0);
#endif
// NOTE: for vertex document, id = _partition
this.Connection.ReplaceOrDeleteDocumentAsync(vertexId, null, vertexId).Wait();
// Update VertexCache
this.Connection.VertexCache.TryRemoveVertexField(vertexId);
return(null);
}